Gas turbines and their structural set-up are generally known. The rotors of gas turbines may in this case be constructed and assembled in various ways. One rotor variant comprises a multiplicity of elements which lie one against the other and are braced via a tie rod extending centrally through the elements. These elements are, on the one hand, rotor disks and, on the other hand, tubular sections, what are known as hollow shafts, which can bear against the rotor disks. The bracing of the rotor disks and hollow shafts is carried out in each case by means of screw nuts screwed on the tie rod on the end faces, the screw nut provided on the compressor side often being designed as a hollow shaft. The rotor disks, bearing one against the other over their area on the end faces, as a rule, carry the moving blades of the turbine and of the compressor on their outer circumferences. Instead of one central tie rod, it is also known to use a plurality of eccentric tie rods.
In order to assemble and dismantle a multipart rotor of this type, an assembly tool is known which comprises essentially two bearing blocks. The two bearing blocks are set up, spaced apart from one another, and the rotor is deposited on them. One of the two bearing blocks, what is known as the turning block, is in this case equipped with a joint which is arranged between the foot and the bearing surface and which is fastened to one end of the rotor. The rotor is therefore placed such that, for example, its compressor-side end can be fastened directly to the joint of the turning block. The other bearing block then supports the rotor on the turbine side. The joint fastened to the turning block serves for transferring the rotor out of the horizontal position into a position perpendicular thereto. For this purpose, a suspension nut is screwed onto the tie rod at the turbine-side end of the rotor. A cable of a crane is fastened to the suspension nut by means of a shackle. While the crane is raising the turbine-side end of the rotor, the compressor-side end rotates about the center of rotation of the joint. The raising operation is concluded when the rotor has reached an approximately vertical position. It is then secured against tipping over by means of a securing device which is also provided on the turning block. As a rule, this securing device comprises a blocking bolt which is provided, above the joint, on the turning block and which blocks the backward movement of the rotor out of the vertical. The suspension nut is subsequently demounted, after which the actual work on the vertically set-up rotor (or tie rod) can then take place.
For assembling the rotor, first the tie rod is set up vertically, and then the individual rotor disks are slipped onto the tie rod in succession, from above, by means of a crane. A turbine-side rotor nut is subsequently screwed on. In the dismantling of a fully assembled rotor, after the latter has been set up vertically, the turbine-side rotor nut is removed, after which the individual rotor disks can be extracted from the tie rod with the aid of a crane. The rotor then comprises essentially only the tie rod.
A similar setting-up device with a turning block is known from German laid-open publication 24 26 231. A first stop is fastened to the foundation centrally below the turning block. In contrast to the abovementioned device, it is not the end of the rotor which is fastened to the turning block, but, instead, a rotor point spaced apart from the end. When the longer rotor section is being raised, the shorter rotor section then pivots toward the foundation. The coupling flange arranged on the shorter rotor section bears against the first stop after the rotor has been set up vertically, after which a second stop is then adapted on the other side of the flange and is connected fixedly via screws to the first stop in order to secure the rotor against tipping over.